DingiShape

 

@interface DingiShape : NSObject <DingiAnnotation, NSSecureCoding>

DingiShape is an abstract class that represents a shape or annotation. Shapes constitute the content of a map – not only the overlays atop the map, but also the content that forms the base map.

Create instances of DingiPointAnnotation, DingiPointCollection, DingiPolyline, DingiMultiPolyline, DingiPolygon, DingiMultiPolygon, or DingiShapeCollection in order to use DingiShape‘s methods. Do not create instances of DingiShape directly, and do not create your own subclasses of this class. The shape classes correspond to the Geometry object types in the GeoJSON standard, but some have nonstandard names for backwards compatibility.

Although you do not create instances of this class directly, you can use its +[DingiShape shapeWithData:encoding:error:] factory method to create one of the concrete subclasses of DingiShape noted above from GeoJSON data. To access a shape’s attributes, use the corresponding DingiFeature class instead.

You can add shapes to the map by adding them to an DingiShapeSource object. Configure the appearance of an DingiShapeSource’s or DingiVectorTileSource’s shapes collectively using a concrete instance of DingiVectorStyleLayer. Alternatively, you can add some kinds of shapes directly to a map view as annotations or overlays.

Creating a Shape

  • Returns an DingiShape object initialized with the given data interpreted as a string containing a GeoJSON object.

    If the GeoJSON object is a geometry, the returned value is a kind of DingiShape. If it is a feature object, the returned value is a kind of DingiShape that conforms to the DingiFeature protocol. If it is a feature collection object, the returned value is an instance of DingiShapeCollectionFeature.

    Example

    let url = mainBundle.url(forResource: "amsterdam", withExtension: "geojson")!
let data = try! Data(contentsOf: url)
let feature = try! DingiShape(data: data, encoding: String.Encoding.utf8.rawValue) as! DingiShapeCollectionFeature

    Declaration

    Objective-C

    + (nullable DingiShape *)shapeWithData:(nonnull NSData *)data
                              encoding:(NSStringEncoding)encoding
                                 error:(NSError *_Nullable *_Nullable)outError;

    Swift

    /*not inherited*/ init(data: Data, encoding: UInt) throws

    Parameters

    data

    String data containing GeoJSON source code.
    encoding

    The encoding used by data.
    outError

    Upon return, if an error has occurred, a pointer to an NSError object describing the error. Pass in NULL to ignore any error.

    Return Value

    An DingiShape object representation of data, or nil if data could not be parsed as valid GeoJSON source code. If nil, outError contains an NSError object describing the problem.

Accessing the Shape Attributes

  • The title of the shape annotation.

    The default value of this property is nil.

    This property is ignored when the shape is used in an DingiShapeSource. To name a shape used in a shape source, create an DingiFeature and add an attribute to the DingiFeature.attributes property.

    Declaration

    Objective-C

    @property (readwrite, copy, nonatomic, nullable) NSString *title;

    Swift

    var title: String? { get set }

  • The subtitle of the shape annotation. The default value of this property is nil.

    This property is ignored when the shape is used in an DingiShapeSource. To provide additional information about a shape used in a shape source, create an DingiFeature and add an attribute to the DingiFeature.attributes property.

    Declaration

    Objective-C

    @property (readwrite, copy, nonatomic, nullable) NSString *subtitle;

    Swift

    var subtitle: String? { get set }

Creating GeoJSON Data

  • Returns the GeoJSON string representation of the shape encapsulated in a data object.

    Declaration

    Objective-C

    - (nonnull NSData *)geoJSONDataUsingEncoding:(NSStringEncoding)encoding;

    Swift

    func geoJSONData(usingEncoding encoding: UInt) -> Data

    Parameters

    encoding

    The string encoding to use.

    Return Value

    A data object containing the shape’s GeoJSON string representation.